Current Electricity

🚗 Sec 4 NA Combined Physics R e s h a r e Document Style C u r r en t E l ec t r i c i t y 1 / 1 Add Source Science Secondary 4 Physics The direction of the flow of electrons is from the negative terminal to the positive terminal. The flow of electric current is in the direction opposite to that of the flow of electrons. Like electrons charges repel each other (for example, an electron has a negative charge and another electron has a negative charge, so they both will repel) Likewise, opposing poles attract, just like a magnet 2/22/25, 10:38 AM Current Electricity https://www.remnote.com/w/63c4983acdbac42fbe812c31/Current-Electricity-XQUC1bBd5ZwcZMh1U 1/11

Flow of Electricity through a Circuit | Electricity and Circuits | Don't Memor ise YouTube The negative terminal of the cell repels the electrons near it, and the electrons which get repelled go in the downwards direction Electron flow is from negative to positive end of the battery and direction of current is from positive to negative ends of the battery The formula of electric current is I = Q / t Where, I Charge, Q Current and t = time The S.I Unit of Current is Ampere A S o , h o w d i d a c o n v en t i o n a l c u r r en t g et i t s n a m e? Before the discovery of electrons, scientists believed that electric current was caused by the movement of positive charges. Although this idea was later proven wrong, the idea remains. This ‘movement ’ of positive charges is called conventional current. Electric current is actually caused by the flow of electrons from the negative terminal to the positive terminal. Ho w d o w e m ea s u r e c u r r en t s ? 2/22/25, 10:38 AM Current Electricity https://www.remnote.com/w/63c4983acdbac42fbe812c31/Current-Electricity-XQUC1bBd5ZwcZMh1U 2/11

An ammeter is used to measure current It should be connected in series to the circuit 2/22/25, 10:38 AM Current Electricity https://www.remnote.com/w/63c4983acdbac42fbe812c31/Current-Electricity-XQUC1bBd5ZwcZMh1U 3/11

O p en a n d c l o s ed c i r c u i t s An open circuit is a circuit in which current is unable to flow due to breaks in the circuit 2/22/25, 10:38 AM Current Electricity https://www.remnote.com/w/63c4983acdbac42fbe812c31/Current-Electricity-XQUC1bBd5ZwcZMh1U 4/11

A closed circuit allows electricity to flow through without any interruptions (but in this diagram, the bulb will not light up due to the least resistance being on the bypass) E l ec t r o m o t i v e F o r c e a n d P o t en t i a l D i f f er en c e The electromotive force (e.m.f) of an electrical energy source is defined as the work done by the source in driving a unit charge around a complete circuit. 2/22/25, 10:38 AM Current Electricity https://www.remnote.com/w/63c4983acdbac42fbe812c31/Current-Electricity-XQUC1bBd5ZwcZMh1U 5/11

Formula where ε = e.m.f. of electrical energy source; W work done (amount of non-electrical energy conver ted to electrical energy); Q amount of charge. The SI unit of e.m.f